1. Field
The present invention relates to a food heat-exchange device and a refrigerator having the same, and, more particularly, to a food heat-exchange device, which is provided in a storage compartment of a refrigerator and serves to enable rapid-freezing or thawing of food, and a refrigerator having the same.
2. Description of the Related Art
In general, a refrigerator includes a refrigerating compartment in which food is kept cool at a temperature above zero, and a freezing compartment in which food is frozen and stored at a sub-zero temperature.
The freezing compartment is generally used to store meat, instant food, and long-term storage food. The food stored in the freezing compartment must be thawed prior to being cooked.
“Freezing and storage” is a storage method in which food is frozen and stored at a low temperature of −10° C. or less, to prevent deterioration thereof.
When freezing food, ice is produced in or between cells thereof. On the basis of the fact that ice produced by freezing water has a greater volume than water, if ice crystals are excessively grown, this causes destruction of the cell membrane (tissue), resulting in deterioration in the taste of thawed food.
To solve the above-described problem with relation to freezing, it is necessary to allow food to rapidly pass a specific temperature band (from 0° C. to −5° C.) that increases production of ice crystals.
“Thawing” is to change frozen food to a room-temperature state. In this case, to reduce damage to food, it is desirable to uniformly thaw the exterior and interior of food at a constant low temperature. Specifically, thawing food at a low temperature (from 0° C. to −2° C.) may prevent deterioration in the taste of food and excessive thawing of food.
However, since conventional refrigerators are adapted to indirectly freeze food by lowering a surrounding temperature of the food, it is difficult to allow the food to rapidly pass the specific temperature band from 0° C. to −5° C.
Although the lower the surrounding temperature of food, the faster the thawing rate, refrigeration cycle efficiency is deteriorated in proportion to the lowering of temperature, resulting in increased consumption of power.
Further, although uniformly thawing the exterior and interior of food at a constant low temperature within a refrigerator is ideal to prevent deterioration in the taste thereof, this deteriorates convenience in use due to an increased thawing time.
Furthermore, when a heating source is used to directly provide food with hot air, etc. in order to reduce a thawing time, such forcible thawing disadvantageously increases consumption of power.